A tape printer which can print images, corresponding to character data or symbol data, on a tape for labels, to be stuck on cassette tapes or files, has been conventionally in practical use. Also a color tape printer which can print color images on a tape has been used practically of late.
Such a color tape printer uses an ink ribbon on which are repeatedly arranged inks for three colors, yellow (Y), magenta (M) and cyan (C), each of which has a constant length. In the color tape printer, a thermal head is heated and driven in accordance with print data to sequentially transfer the inks for the three colors held by the ink ribbon to the tape, so that the transferred inks are overlapped. Thus, a color image is printed on the tape. When this color tape printer prints an image with the colored ink, the tape and the ink ribbon are carried in the same direction, then only the tape is carried in the reverse direction before the image is printed using the next ink color so that the print start position is adjusted. In this color tape printer, the color tape printer carries the ink ribbon in one direction.
The maximum length of the color printing accomplished by the color tape printer (hereinafter referred as the maximum print length) during one printing operation (the transference of the inks for three colors, Y, M and C, are performed once, respectively) corresponds to the length of each of the colored inks. That is, if the inks for Y, M and C are repeatedly arranged on the ink ribbon at intervals of 10 cm, the maximum length of the color printing for one printing operation is 10 cm.
When the length of an image, corresponding to print data prepared with the tape printer, to be printed on the tape in the lengthwise direction equals the length of each of the inks arranged on the ink ribbon, the image corresponding to the print data can be printed while using the inks for Y, M and C so that unused inks do not remain.
However, when the length of an image to be printed is shorter than the maximum print length, the colored inks on the ink ribbon are only partially used because the ink ribbon is carried in the one direction. As a result, unused inks remain on the ink ribbon. Especially when the tape printer prints many short images, the quantity of unused inks remaining on the ink ribbon increases.